From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Frederic Sowa Subject: Re: [PATCH v5] ipv6:introduce function to find route for redirect Date: Wed, 4 Sep 2013 20:36:02 +0200 Message-ID: <20130904183602.GA13136@order.stressinduktion.org> References: <52271D15.1000806@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: davem@davemloft.net, netdev@vger.kernel.org To: Duan Jiong Return-path: Received: from order.stressinduktion.org ([87.106.68.36]:37649 "EHLO order.stressinduktion.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755519Ab3IDSgE (ORCPT ); Wed, 4 Sep 2013 14:36:04 -0400 Content-Disposition: inline In-Reply-To: <52271D15.1000806@cn.fujitsu.com> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, Sep 04, 2013 at 07:44:21PM +0800, Duan Jiong wrote: > From: Duan Jiong > > RFC 4861 says that the IP source address of the Redirect is the > same as the current first-hop router for the specified ICMP > Destination Address, so the gateway should be taken into > consideration when we find the route for redirect. > > There was once a check in commit > a6279458c534d01ccc39498aba61c93083ee0372 ("NDISC: Search over > all possible rules on receipt of redirect.") and the check > went away in commit b94f1c0904da9b8bf031667afc48080ba7c3e8c9 > ("ipv6: Use icmpv6_notify() to propagate redirect, instead of > rt6_redirect()"). > > The bug is only "exploitable" on layer-2 because the source > address of the redirect is checked to be a valid link-local > address but it makes spoofing a lot easier in the same L2 > domain nonetheless. > > Thanks very much for Hannes's help. > > Signed-off-by: Duan Jiong Tested and looks good! Thanks! Acked-by: Hannes Frederic Sowa